Adjustable shelf



FIG. 1 is a top perspective view of the adjustable shelf;

FIG. 2 is a front elevational view of the adjustable shelf;

FIG. 3 is a right side elevational view of the adjustable shelf;

FIG. 4 is a left side elevational view of the adjustable shelf;

FIG. 5 is a top view of the adjustable shelf;

FIG. 6 is a bottom view of the adjustable shelf;

FIG. 7 is a top perspective view of a bracket of the adjustable shelf;

FIG. 8 is a front elevational view of a bracket of the adjustable shelf;

FIG. 9 is a right side elevational view of a bracket of the adjustable shelf;

FIG. 10 is a left side elevational view of a bracket of the adjustable shelf;

FIG. 11 is a top view of a bracket of the adjustable shelf;

FIG. 12 is a bottom view of a bracket of the adjustable shelf; and,

FIG. 13 is a bottom perspective view of a bracket of the adjustable shelf. 

CLAIM The ornamental design for an adjustable shelf, as shown. 